Double-length jaw system for electrosurgical instrument

ABSTRACT

An electrosurgical forceps includes a handle having a shaft extending therefrom defining a longitudinal axis. The handle is selectively movable to translate movement of the shaft along the longitudinal axis to actuate a pair of laterally spaced first and second jaw members pivotably connected to a distal end of the shaft. The first and second jaw members are moveable from an open position, wherein the first and second jaw members are in spaced relation relative to a stationary jaw member, to a closed position wherein the first and second jaw members cooperate with the stationary jaw member to grasp tissue therebetween. Each of the jaw members is adapted to connect to an electrosurgical energy source to conduct energy through tissue grasped therebetween to effect a tissue seal.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent application Ser. No. 13/834,703, filed on Mar. 15, 2013, which claims the benefit of and priority to U.S. Provisional Application Ser. No. 61/664,492, filed on Jun. 26, 2012, the entire contents of each of which are incorporated herein by reference.

BACKGROUND

1. Technical Field

The following disclosure relates to an apparatus, system, and method for performing an electrosurgical procedure and, more particularly, to an apparatus, system and method that utilizes energy to seal and/or divide tissue.

2. Description of Related Art

Electrosurgical apparatuses (e.g., electrosurgical forceps) are well known in the medical arts and typically include a handle, a shaft, and an end effector assembly operatively coupled to a distal end of the shaft that is configured to manipulate tissue (e.g., grasp and seal tissue). Electrosurgical forceps utilize both mechanical clamping action and electrical energy to effect hemostasis by heating the tissue and blood vessels to coagulate, cauterize, seal, cut, desiccate, and/or fulgurate tissue

As an alternative to open electrosurgical forceps for use with open surgical procedures, many modern surgeons use endoscopes and endoscopic electrosurgical apparatus (e.g., endoscopic forceps) or laparoscopic forceps for remotely accessing organs through smaller, puncture-like incisions. As a direct result thereof, patients tend to benefit from less scarring, fewer infections, shorter hospital stays, less pain, less restriction of activity, and reduced healing time. Typically, the forceps are inserted into the patient through one or more various types of cannulas or access ports (typically having an opening that ranges from about five millimeters to about twelve millimeters) that has been made with a trocar. As such, smaller cannulas are typically more desirable relative to larger cannulas. Forceps that are configured for use with small cannulas (e.g., cannulas less than five millimeters) may present design challenges for a manufacturer of electrosurgical instruments.

SUMMARY

According to one aspect of the present disclosure, an electrosurgical forceps is provided. The electrosurgical forceps includes a handle having a shaft extending therefrom defining a longitudinal axis. The handle is selectively movable to translate movement of the shaft along the longitudinal axis to actuate a pair of laterally spaced first and second jaw members pivotably connected to a distal end of the shaft. The first and second jaw members are moveable from an open position, wherein the first and second jaw members are in spaced relation relative to a stationary jaw member, to a closed position wherein the first and second jaw members cooperate with the stationary jaw member to grasp tissue therebetween. Each of the jaw members is adapted to connect to an electrosurgical energy source to conduct energy through tissue grasped therebetween to effect a tissue seal.

Alternatively or in addition, an inner shaft is axially disposed within the shaft and fixedly coupled to the stationary jaw member. The shaft may be configured to slide over the inner shaft upon movement along the longitudinal axis.

Alternatively or in addition, at least one of the first and second jaw members may be pivotally coupled to a distal end of the stationary jaw member.

Alternatively or in addition, movement of the shaft along the longitudinal axis may be configured to pivot the first and second jaw members substantially simultaneously between the open and closed positions.

Alternatively or in addition, distal movement of the shaft may be configured to actuate the jaw members to the closed position.

Alternatively or in addition, proximal movement of the shaft may be configured to actuate the jaw members to the open position.

Alternatively or in addition, the first and second jaw members may be disposed vertically offset from the stationary jaw member such that at least a portion of each of the first and second jaw members substantially aligns in vertical registration with at least a portion of the stationary jaw member when the jaw members are in the closed position.

Alternatively or in addition, an electrically conductive tissue sealing plate may be operatively coupled to each of the jaw members. The electrically conductive tissue sealing plates may be adapted to connect to the electrosurgical energy source to conduct energy through tissue grasped between the jaw members to effect the tissue seal.

Alternatively or in addition, the first and second jaw members may be disposed vertically offset from the stationary jaw member such that at least a portion of the electrically conductive tissue sealing plates of each of the first and second jaw members substantially aligns in vertical registration with at least a portion of the electrically conductive tissue sealing plate of the stationary jaw member when the jaw members are in the closed position.

Alternatively or in addition, at least one of the first and second jaw members may be generally L-shaped.

Alternatively or in addition, at least one of the first and second jaw members may be pivotally coupled to the shaft via a linkage. The linkage may be pivotally coupled to the shaft and configured to control a closing angle of the at least one jaw member relative to the stationary jaw member such that the at least one jaw member is disposed substantially parallel to the stationary jaw member when the jaw members are in the closed position.

According to a further aspect of the present disclosure, an electrosurgical forceps is provided. The electrosurgical forceps includes a handle having a shaft extending therefrom defining a longitudinal axis. The handle is selectively movable to translate movement of the shaft along the longitudinal axis to actuate a pair of laterally spaced first and second jaw members pivotably connected to a distal end of the shaft. The first and second jaw members are moveable from an open position, wherein the first and second jaw members are in spaced relation relative to an opposing jaw member, to a closed position wherein the first and second jaw members cooperate with the opposing jaw member to grasp tissue therebetween. The first and second jaw members are vertically offset from the opposing jaw member such that at least a portion of each of the first and second jaw members substantially aligns in vertical registration with at least a portion of the opposing jaw member. Each of the jaw members is adapted to connect to an electrosurgical energy source to conduct energy through tissue grasped therebetween to effect a tissue seal.

Alternatively or in addition, proximal movement of the shaft may be configured to rotate the first jaw member counter clock-wise away from the opposing jaw member and the second jaw member clock-wise away from the opposing jaw member.

Alternatively or in addition, distal movement of the shaft may be configured to rotate the first jaw member clock-wise toward the opposing jaw member and the second jaw member counter clock-wise toward the opposing jaw member.

Alternatively or in addition, the opposing jaw member may be stationary.

Alternatively or in addition, an inner sleeve may be axially disposed within the shaft and fixedly coupled to the opposing jaw member. The shaft may be configured to slide over the inner shaft upon movement along the longitudinal axis.

Alternatively or in addition, the opposing jaw member may form a distal end of the inner sleeve.

According to a further aspect of the present disclosure, a method of performing an electrosurgical procedure is provided. The method includes the step of providing an electrosurgical forceps. The electrosurgical forceps includes a handle having a shaft extending therefrom defining a longitudinal axis. The handle is selectively movable to translate movement of the shaft along the longitudinal axis to actuate a pair of laterally spaced first and second jaw members pivotably connected to a distal end of the shaft. The first and second jaw members are moveable from an open position, wherein the first and second jaw members are in spaced relation relative to a stationary jaw member, to a closed position wherein the first and second jaw members cooperate with the stationary jaw member to grasp tissue therebetween. Each of the jaw members is adapted to connect to an electrosurgical energy source. The method also includes the steps of selectively moving the handle to translate movement of the shaft along the longitudinal axis to move the first and second jaw members from the open position to the closed position to grasp tissue therebetween and delivering electrosurgical energy from the electrosurgical energy source to each of the jaw members to effect a tissue seal.

Alternatively or in addition, the selectively moving step may include rotating the first jaw member clock-wise toward the stationary jaw member and the second jaw member counter clock-wise toward the stationary jaw member.

Alternatively or in addition, the first and second jaw members may be vertically offset from the stationary jaw member such that at least a portion of each of the first and second jaw members substantially aligns in vertical registration with at least a portion of the stationary jaw member.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the present disclosure are described hereinbelow with references to the drawings, wherein:

FIG. 1 is a perspective view of an endoscopic bipolar forceps showing a housing, a shaft, and an end effector assembly in accordance with an embodiment of the present disclosure;

FIG. 2A is a schematic, side elevational view of the end effector assembly of FIG. 1 with the jaw members in open configuration;

FIG. 2B is a schematic, side elevational view of the end effector assembly of FIG. 1 with the jaw members in a closed configuration;

FIG. 3A is a schematic, side elevational view of an end effector assembly according to another embodiment of the present disclosure, with the jaw members in an open configuration;

FIG. 3B is a schematic, side elevational view of the end effector assembly of FIG. 3A, with the jaw members in a closed configuration; and

FIG. 4 is an enlarged, rear, perspective view of the end effector assembly of FIG. 1 shown grasping tissue.

DETAILED DESCRIPTION

Detailed embodiments of the present disclosure are disclosed herein, however, the disclosed embodiments are merely examples of the disclosure, which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present disclosure in virtually any appropriately detailed structure.

As noted above, it may prove useful in the arts to provide an electrosurgical apparatus that is suitable for use during catheter-based endoluminal procedures and/or for use with various access ports, including but not limited to those that are greater than and/or less than five millimeters. The present disclosure may be particularly advantageous for use with flexible-shafted instrument designs, such as catheter-based designs used in endoluminal procedures. With this purpose in mind, the present disclosure includes an electrosurgical forceps that includes jaw members associated with an end effector assembly of the electrosurgical forceps. The jaw members are operably coupled to an electrosurgical energy source and are each configured to conduct an electrical potential (e.g., positive or negative) therethrough that may be the same or opposite to that of the other jaw member(s) (e.g., in a bipolar configuration). In some embodiments, a shaft mechanically cooperates with a handle assembly and at least one of the jaw members to move the jaw members between an open configuration to a closed configuration. In the closed configuration, the jaw members utilize tissue grasped therebetween to form a closed loop electrical circuit such that a desired tissue effect (e.g., tissue seal) may be achieved.

Turning now to FIG. 1, an embodiment of an endoscopic bipolar forceps 10 is shown for use with various surgical procedures and generally includes a housing 20, a handle assembly 30, a rotating assembly 80, a trigger assembly 70, and an end effector assembly 100 that mutually cooperate to grasp, seal, and divide tubular vessels and vascular tissue. Although the majority of the figure drawings depict a bipolar forceps 10 for use in connection with endoscopic surgical procedures, the present disclosure may be used for more traditional open surgical procedures. For the purposes herein, the forceps 10 is described in terms of an endoscopic instrument, however, it is contemplated that a version of the forceps for “open” procedures may also include the same or similar operating components and features as described below.

In the drawings and in the descriptions that follow, the term “proximal”, as is traditional, will refer to the end of the forceps 10 that is closer to the user, while the term “distal” will refer to the end that is farther from the user.

Forceps 10 includes a shaft 12 that has a distal end 14 configured to mechanically engage the end effector assembly 100 and a proximal end 16 that mechanically engages the housing 20. Proximal end 16 of shaft 12 is received within housing 20 and appropriate mechanical and electrical connections relating thereto are established.

Forceps 10 includes an electrosurgical cable 310 that connects the forceps 10 to a source of electrosurgical energy, e.g., a generator (not shown). One such source of electrosurgical energy is described in commonly-owned U.S. Pat. No. 6,033,399 entitled “ELECTROSURGICAL GENERATOR WITH ADAPTIVE POWER CONTROL”. Cable 310 is internally divided into several cable leads (not shown) that each transmit electrical potentials through their respective feed paths through the forceps 10 to the end effector assembly 100.

For a more detailed description of handle assembly 30, movable handle 40, rotating assembly 80, and electrosurgical cable 310 (including line-feed configurations and/or connections) reference is made to commonly owned Patent Publication No. 2003/0229344, filed on Feb. 20, 2003, entitled VESSEL SEALER AND DIVIDER AND METHOD OF MANUFACTURING THE SAME.

Handle assembly 30 includes a fixed handle 50 and a movable handle 40. Fixed handle 50 is integrally associated with housing 20 and handle 40 is movable relative to fixed handle 50 as explained in more detail below with respect to the operation of the forceps 10. Rotating assembly 80 is operatively connected to the housing 20 and is rotatable in either direction about a longitudinal axis “X-X” (See FIG. 1).

End effector assembly 100 is attached to the distal end 14 of shaft 12 and includes a pair of laterally spaced jaw members 110 a and 110 b that are configured to pivot relative to an opposing stationary jaw member 120. Movable handle 40 is operatively connected to shaft 12, which mechanically cooperate to impart movement of the jaw members 110 a and 110 b from an open position (FIG. 2A) wherein the jaw members 110 a and 110 b are disposed in spaced relation relative to the opposing stationary jaw member 120, to a clamping or closed position (FIG. 2B) wherein the jaw members 110 a and 110 b cooperate with stationary jaw member 120 to grasp tissue therebetween for sealing purposes. During movement of jaw members 110 a, 110 b from the open position to the closed position, jaw members 110 a, 110 b pivot toward each other, i.e., jaw member 110 a pivots clock-wise toward stationary jaw member 120 and jaw member 110 b pivots counter clock-wise toward stationary jaw member 120. During movement of jaw members 110 a, 110 b from the closed position to the open position, jaw members 110 a, 110 b pivot away from each other, i.e., jaw member 110 a pivots counter clock-wise away from stationary jaw member 120 and jaw member 110 b pivots clock-wise away from stationary jaw member 120. With this purpose in mind, forceps 10 may include any suitable number of configurations, components, mechanical connections, and/or components (e.g., gears, links, springs, rods, etc.), and/or electro-mechanical connections, configurations, and/or components such that forceps 10 may function as intended.

In some embodiments, forceps 10 may be configured such that it is re-usable or such that it is fully or partially disposable depending upon a particular purpose or to achieve a particular result. For example, end effector assembly 100 may be selectively and releasably engageable with the distal end 14 of shaft 12 and/or the proximal end 16 of shaft 12 may be selectively and releasably engageable with the housing 20 and the handle assembly 30. In either of these two instances, the forceps 10 would be considered “partially disposable” or “reposable”, e.g., a new or different end effector assembly 100 (or end effector assembly 100 and shaft 12) selectively replaces the old end effector assembly 100 as needed.

As best shown in FIGS. 2A and 2B, jaw members 110 a, 110 b also include a jaw housing 116 a, 116 b, respectively, that has a respective insulative substrate or insulator 114 a, 114 b and an electrically conducive sealing surface 112 a, 112 b. Insulators 114 a, 114 b are configured to secure the electrically conductive sealing surfaces 112 a, 112 b, respectively, to respective jaw housings 116 a, 116 b. This may be accomplished by overmolding insulators 114 a, 114 b about jaw housings 116 a, 116 b, respectively, or by other suitable methods such as using adhesives.

Stationary jaw member 120 includes similar elements to jaw members 110 a, 110 b such as a jaw housing 126 having an insulator 124 and an electrically conductive sealing surface 122 that is secured to the jaw housing 126 by the insulator 124. This may be accomplished, for example, by overmolding insulator 124 about jaw housing 126, or by other suitable methods such as using adhesives.

The illustrated embodiment of FIGS. 2A and 2B is illustrative only in that any one or more of jaw members 110 a, 110 b or 120 may be configured to be devoid of an insulating substrate 114 a, 114 b or 124. For example, in some embodiments, jaw members 110 a, 110 b may include insulating substrate 114 a, 114 b, respectively, and stationary jaw member 120 may be configured such that insulating substrate 124 is removed and/or end effector assembly 100 may be manufactured such that stationary jaw member 120 does not include an insulating substrate. The insulators 114 a, 114 b, 124, electrically conductive sealing surfaces 112, 112 b, 122, and the jaw housings 116, 126 are configured to limit and/or reduce many of the known undesirable effects related to tissue sealing, e.g., flashover, thermal spread, and stray current dissipation. In other embodiments, the jaw members 110 a, 110 b, and 120 may be manufactured from a ceramic-like material and the electrically conductive surfaces 112 a, 112 b, and 122 are coated onto the ceramic-like jaw members 110 a, 110 b, and 120, respectively.

The end effector assembly 100 may be designed as a unilateral assembly, i.e., stationary jaw member 120 is fixed relative to the shaft 12 and jaw members 110 a and 110 b pivot about respective pivot pins 103 a and 103 b relative to stationary jaw member 120 to grasp tissue, or as a bilateral assembly, i.e., jaw members 110 a, 110 b and stationary jaw member 120 pivot relative to each other to grasp tissue. In some embodiments and as will be discussed in further detail below, jaw members 110 a, 110 b are laterally spaced apart along a distally extended portion 13 of the distal end 14 of shaft 12 and are rotatable about pivot pins 103 a and 103 b, respectively, such that jaw members 110 a, 110 b pivot relative to stationary jaw member 120 for purposes of grasping tissue therebetween. In the illustrated embodiment of FIGS. 2A and 2B, jaw member 110 b is generally linear in configuration and jaw member 110 a is generally L-shaped.

With continued reference to FIGS. 2A and 2B, end effector assembly 100 includes one stationary jaw member 120 mounted in fixed relation to an inner shaft 60 that is coaxially disposed within the shaft 12. In some embodiments, stationary jaw member 120 is monolithically formed with inner shaft 60 such that stationary jaw member 120 forms a distal end of inner shaft 60. Jaw member 110 b is pivotally coupled by way of pivot pin 103 b to a linkage 140 that, in turn, couples to a distal end 108 of the extended portion 13 of shaft 12 via a pivot pin 105. Stationary jaw member 120 includes a generally L-shaped distal end 123 to which jaw member 110 b is pivotally coupled via a pivot pin 107.

Jaw member 110 a is pivotally coupled to a proximal portion of the stationary jaw member 120 via pivot pin 103 a. As discussed above, jaw member 110 a is generally L-shaped in the illustrated embodiment of FIGS. 2A and 2B. A linkage 130 is operably coupled by way of a pivot pin 101 to or substantially proximate to the vertex of the generally L-shaped jaw member 110 a and, in turn, couples to the shaft 12 via a pivot pin 102 to effectively couple jaw member 110 a to the shaft 12.

Shaft 12 is slidingly disposed about inner shaft 60 and is remotely operable by handle assembly 30 to translate movement of shaft 12 relative to inner shaft 60 along longitudinal axis “X-X”. In order to open end effector assembly 100, shaft 12 is withdrawn or pulled in a proximal direction (see FIG. 2A), by actuating movable handle 40 relative to fixed handle 50. In order to close end effector assembly 100, shaft 12 is pushed or moved in a distal direction (see FIG. 2B), by actuating movable handle 40 relative to fixed handle 50. By way of example, moving shaft 12 in the proximal direction, as depicted in FIG. 2A, may be effected by squeezing movable handle 40 toward stationary handle 50. In this scenario, moving shaft 12 in the distal direction, as depicted in FIG. 2B, may be effected by approximating movable handle 40 away from stationary handle 50. In some embodiments, the configuration described in the above scenario may be reversed, e.g., squeezing movable handle 40 will move shaft 12 in the distal direction and approximating movable handle 40 away from stationary handle 50 will move shaft 12 in the proximal direction.

Jaw members 110 a and 110 b are actuated into the closed position by sliding the shaft 12 axially over inner shaft 60 in the distal direction such that jaw member 110 a pivots about pivot pins 101 and 103 a toward stationary jaw member 120 and jaw member 110 b rotates about pivot pins 103 b and 107 toward stationary jaw member 120, as depicted in FIG. 2B. In this manner, pushing shaft 12 distally closes jaw members 110 a and 110 b substantially simultaneously and, in conjunction with sealing surface 122, creates an effective tissue sealing area at least the size of tissue sealing surface 122. Counter clock-wise rotation of jaw member 110 b about pivot pins 103 b and 107 is aided by counter clock-wise rotation of linkage 140 about pivot pin 105 as shaft 12 is slid distally. More specifically, as linkage 140 rotates counter clock-wise about pivot pin 105, the angle of closure of jaw member 110 b relative to stationary jaw member 120 is decreased so that as jaw member 110 b moves into the closed position such that sealing surface 112 b is disposed in a substantially parallel configuration relative to sealing surface 122, as depicted in FIG. 2B.

Jaw members 110 a and 110 b are actuated into the open position by sliding the shaft 12 axially over inner shaft 60 in the proximal direction such that jaw member 110 a pivots about pivot pins 101 and 103 a away from stationary jaw member 120 and jaw member 110 b rotates about pivot pins 103 b and 107 away from stationary jaw member 120, as depicted in FIG. 2B. In this manner, pulling shaft 12 proximally opens jaw members 110 a and 110 b substantially simultaneously. Clock-wise rotation of jaw member 110 b about pivot pins 103 b and 107 is aided by clock-wise rotation of linkage 140 about pivot pin 105 as shaft 12 is slid proximally.

As described above, the dual pivoting of jaw members 110 a, 110 b relative to stationary jaw member 120 operates to increase (e.g., double) the effective tissue sealing area between jaw members 110 a, 110 b and stationary jaw member 120. In some embodiments, sealing surfaces 112 a and 112 b may each be substantially half of the length of sealing surface 122 such that upon closure of jaw members 110 a and 110 b, sealing surfaces 112 a, 112 b are substantially equal to the length of sealing surface 122 to provide a relatively larger effective tissue sealing area with respect to a conventional pair of opposing tissue grasping jaw members. In this manner, stationary jaw member 120 may be manufactured with increased length relative to conventional jaw members to create a larger and/or longer effective tissue sealing surface relative to sealing surfaces of conventional surgical forceps.

As best shown in FIG. 2B, jaw members 110 a and 110 b are disposed generally adjacent to stationary jaw member 120 or are at least partially vertically offset from stationary jaw member 120. However, when jaw members 110 a, 110 b are in the closed position, as shown in FIG. 2B, at least a portion of jaw members 110 a, 110 b overlaps or substantially aligns in vertical registration with at least a portion of stationary jaw member 120. In some embodiments, tissue sealing surfaces 110 a, 110 b and 122 are disposed on respective jaw members 110 a, 110 b, and 120 in such a way so that when jaw members 110 a, 110 b are in the closed position, as shown in FIG. 2B, at least a portion of tissue sealing surfaces 112 a and 112 b overlaps or substantially aligns in vertical registration with tissue sealing surface 122 to form the effective tissue sealing surface area between jaw members 110 a, 110 b and stationary jaw member 120.

Turning now to FIGS. 3A and 3B, another embodiment of forceps 10 including an end effector assembly 200, in accordance with the present disclosure, is shown and described. End effector assembly 200 may include some, if not all, of the features and elements associated with end effector assembly 100 and as described above with reference to FIGS. 2A and 2B. End effector assembly 200 is substantially as described above with respect to end effector assembly 100 of FIGS. 1, 2A, and 2B and will only be described to the extent necessary to disclose the differences between the embodiments. While end effector assembly 200 is shown as having a unilateral jaw member arrangement, end effector assembly 200 may, in certain embodiments, have a bilateral jaw member arrangement.

As shown in FIGS. 3A and 3B, end effector assembly 200 includes opposing jaw members 110 a and 110 b having electrically conductive tissue sealing surfaces 112 a and 112 b, respectively. Jaw members 110 a and 110 b cooperate with stationary jaw member 120 to grasp tissue therebetween, as substantially described above with respect to the embodiment of FIGS. 2A and 2B. In the illustrated embodiment of FIGS. 2A and 2B, jaw member 110 b is generally linear in configuration. The jaw member 110 b shown in FIGS. 3A and 3B differs from jaw member 110 b shown in FIGS. 2A and 2B in that the jaw member 110 b of FIGS. 3A and 3B is generally L-shaped similar to jaw member 110 a of FIGS. 2A and 2B.

With continued reference to FIGS. 3A and 3B, the generally L-shaped configuration of jaw member 110 b causes the angle of closure of jaw member 110 b relative to stationary jaw member 120 to increase such that jaw member 110 b is permitted to rotate about pivot pins 103 b and 107 toward stationary jaw member 120 so that sealing surface 112 b is positioned substantially parallel to sealing surface 120 when jaw member 110 b is in the closed position, as depicted in FIG. 3B.

In some embodiments, either or both of jaw members 110 a and 110 b may include a cam slot configuration (not shown) to facilitate actuation of jaw members 110 a and 110 b. In this scenario, for example, jaw member 110 a may include a cam slot in which pivot pin 102 translates relative to the shaft 12 upon rotational movement of jaw member 110 a about pivot pin 103 a to improve the opening and closing motion of jaw member 110 a. The location where pivot pin 102 couples to the shaft 12 may also be modified from the illustrated embodiments to improve the opening and closing motion of jaw member 110 a. Likewise, jaw member 110 b may include a cam slot in which pivot pin 105 and/or 103 btranslates upon rotational movement of jaw member 110 b about pivot pin 107. In some embodiments, although not explicitly shown in the illustrated embodiments, the above described cam slot configuration may replace linkage 140 such that pivot pin 105 connects the distal end 108 of the extended portion 13 to jaw member 110 b and translates within a cam slot upon rotational movement of jaw member 110 b. The location where pivot pin 105 couples to the extended portion 13 may also be modified from the illustrated embodiments to improve the opening and closing motion of jaw member 110 b.

FIG. 4 shows forceps 10 grasping tissue. As the handle 40 is squeezed, jaw members 110 a and 110 b are approximated toward stationary jaw member 120 to a clamped or closed position about tissue. Once jaws members 110 a and 110 b are fully compressed about the tissue, forceps 10 is now ready for selective application of electrosurgical energy and subsequent separation of the tissue. By controlling the intensity, frequency, and duration of the electrosurgical energy applied to tissue, the operator can either cauterize, coagulate/desiccate, seal, cut, and/or simply reduce or slow bleeding. Two mechanical factors play an important role in determining the resulting thickness of the sealed tissue and effectiveness of the seal, i.e., the pressure applied between opposing jaw members 110 a, 110 b and 120 and the gap distance “G” between the opposing sealing surfaces 112 a, 112 b and 122 of the jaw members 110 a, 110 b and 120 during the sealing process.

At least one jaw member (e.g., stationary jaw member 120) may include a stop member (not shown) extending a predetermined distance from the sealing surface 112 a, 112 b, or 122 that limits the movement of opposing jaw members 110 a, 110 b relative to stationary jaw member 120. The predetermined distance may be according to the specific material properties (e.g., compressive strength, thermal expansion, etc.) of the stop member(s) to yield a consistent and accurate gap distance “G” during sealing (FIG. 4). In some embodiments, the gap distance between opposing sealing surfaces 112 a, 112 b and 122 during sealing ranges from about 0.001 inches to about 0.006 inches and, in other embodiments, between about 0.002 and about 0.003 inches. Several suitable thermal spraying techniques may be utilized including, for example, depositing a broad range of heat resistant and insulative materials on various surfaces to create stop members for controlling the gap distance between electrically conductive surfaces 112 a, 112 b and 122.

While several embodiments of the disclosure have been shown in the drawings, it is not intended that the disclosure be limited thereto, as it is intended that the disclosure be as broad in scope as the art will allow and that the specification be read likewise. Therefore, the above description should not be construed as limiting, but merely as exemplifications of particular embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the claims appended hereto. 

What is claimed is:
 1. An end effector assembly, comprising: a stationary jaw member defining a longitudinal axis and having a proximal end and a distal end; a first jaw member disposed adjacent the proximal end of the stationary jaw member; and a second jaw member disposed adjacent the distal end of the stationary jaw member and laterally spaced from the first jaw member along the longitudinal axis of the stationary jaw member, wherein the first and second jaw members are each configured to move relative to the stationary jaw member between an open position, wherein at least a portion of each of the first and second jaw members are spaced relative to the stationary jaw member, and a closed position, wherein the first and second jaw members cooperate with the stationary jaw member to grasp tissue between the stationary jaw member and at least one of the first or second jaw members, wherein the first jaw member is pivotably coupled to the proximal end of the stationary jaw member, and the second jaw member is pivotably coupled to the distal end of the stationary jaw member.
 2. The end effector assembly according to claim 1, wherein upon movement of the first and second jaw members from the open position to the closed position, the first jaw member pivots relative to the proximal end of the stationary jaw member in a first rotational direction, and the second jaw member pivots relative to the distal end of the stationary jaw member in a second rotational direction, opposite the first rotational direction.
 3. The end effector assembly according to claim 1, further comprising: a first linkage having a first end pivotably coupled to the first jaw member and a second end configured to be pivotably coupled to a shaft; and a second linkage having a first end pivotably coupled to the second jaw member and a second end configured to be pivotably coupled to the shaft.
 4. The end effector assembly according to claim 1, wherein the distal end of the stationary jaw member is L-shaped.
 5. The end effector assembly according to claim 1, wherein at least one of the first jaw member or the second jaw member is L-shaped.
 6. The end effector assembly according to claim 1, wherein in the open position, the first and second jaw members are substantially perpendicular to the stationary jaw member, and in the closed position, the first and second jaw members are substantially parallel with the stationary jaw member.
 7. The end effector assembly according to claim 1, wherein the stationary jaw member includes: a jaw housing; an insulator disposed on the jaw housing; and a conductive sealing surface disposed on the insulator.
 8. The end effector assembly according to claim 7, wherein the first and second jaw members each have a conductive sealing surface having a first length, the conductive sealing surface of the stationary jaw member having a second length substantially equal to twice the first length.
 9. An end effector assembly, comprising: a stationary jaw member having a proximal end and a distal end; a first jaw member having a first end pivotably coupled to the proximal end of the stationary jaw member and a second end; a second jaw member having a first end pivotably coupled to the distal end of the stationary jaw member and a second end, the first ends of the first and second jaw members being longitudinally spaced from one another along the stationary jaw member, a first linkage having a first end pivotably coupled to the first jaw member and a second end configured to be pivotably coupled to a shaft; and a second linkage having a first end pivotably coupled to the second jaw member and a second end configured to be pivotably coupled to the shaft.
 10. The end effector assembly according to claim 9, wherein the first and second jaw members are configured to be movable relative to the stationary jaw member between an open position, wherein the second ends of the first and second jaw members are spaced relative to the stationary jaw member, and a closed position, wherein the second ends of the first and second jaw members approximate the stationary jaw member.
 11. The end effector assembly according to claim 10, wherein upon movement of the first and second jaw members from the open position to the closed position, the first jaw member pivots relative to the proximal end of the stationary jaw member in a first rotational direction, and the second jaw member pivots relative to the distal end of the stationary jaw member in a second rotational direction, opposite the first rotational direction.
 12. The end effector assembly according to claim 10, wherein in the open position, the first and second jaw members are substantially perpendicular to the stationary jaw member, and in the closed position, the first and second jaw members are substantially parallel with the stationary jaw member.
 13. The end effector assembly according to claim 9, wherein the distal end of the stationary jaw member is L-shaped.
 14. The end effector assembly according to claim 9, wherein at least one of the first jaw member or the second jaw member is L-shaped.
 15. The end effector assembly according to claim 9, wherein the stationary jaw member includes: a jaw housing; an insulator disposed on the jaw housing; and a conductive sealing surface disposed on the insulator.
 16. The end effector assembly according to claim 15, wherein the first and second jaw members each have a conductive sealing surface having a first length, the conductive sealing surface of the stationary jaw member having a second length substantially equal to twice the first length.
 17. An end effector assembly, comprising: a stationary jaw member defining a longitudinal axis and having a proximal end and a distal end; a first jaw member disposed adjacent the proximal end of the stationary jaw member; and a second jaw member disposed adjacent the distal end of the stationary jaw member and laterally spaced from the first jaw member along the longitudinal axis of the stationary jaw member, wherein the first and second jaw members are each configured to move relative to the stationary jaw member between an open position, wherein at least a portion of each of the first and second jaw members are spaced relative to the stationary jaw member, and a closed position, wherein the first and second jaw members cooperate with the stationary jaw member to grasp tissue between the stationary jaw member and at least one of the first or second jaw members; a first linkage having a first end pivotably coupled to the first jaw member and a second end configured to be pivotably coupled to a shaft; and a second linkage having a first end pivotably coupled to the second jaw member and a second end configured to be pivotably coupled to the shaft.
 18. An end effector assembly, comprising: a stationary jaw member defining a longitudinal axis and having a proximal end and a distal end; a first jaw member disposed adjacent the proximal end of the stationary jaw member; and a second jaw member disposed adjacent the distal end of the stationary jaw member and laterally spaced from the first jaw member along the longitudinal axis of the stationary jaw member, wherein the first and second jaw members are each configured to move relative to the stationary jaw member between an open position, wherein at least a portion of each of the first and second jaw members are spaced relative to the stationary jaw member, and a closed position, wherein the first and second jaw members cooperate with the stationary jaw member to grasp tissue between the stationary jaw member and at least one of the first or second members, wherein in the open position, the first and second jaw members are substantially perpendicular to the stationary jaw member, and in the closed position, the first and second jaw members are substantially parallel with the stationary jaw member.
 19. An end effector assembly, comprising: a stationary jaw member defining a longitudinal axis and having a proximal end and a distal end; a first jaw member disposed adjacent the proximal end of the stationary jaw member; and a second jaw member disposed adjacent the distal end of the stationary jaw member and laterally spaced from the first jaw member along the longitudinal axis of the stationary jaw member, wherein the first and second jaw members are each configured to move relative to the stationary jaw member between an open position, wherein at least a portion of each of the first and second jaw members are spaced relative to the stationary jaw member, and a closed position, wherein the first and second jaw members cooperate with the stationary jaw member to grasp tissue between the stationary jaw member and at least one of the first or second members, wherein the first and second jaw members each have a conductive sealing surface having a first length, the conductive sealing surface of the stationary jaw member having a second length substantially equal to twice the first length.
 20. An end effector assembly, comprising: a stationary jaw member having a proximal end and a distal end; a first jaw member having a first end pivotably coupled to the proximal end of the stationary jaw member and a second end; and a second jaw member having a first end pivotably coupled to the distal end of the stationary jaw member and a second end, the first ends of the first and second jaw members being longitudinally spaced from one another along the stationary jaw member, wherein at least one of the first jaw member or the second jaw member is L-shaped.
 21. An end effector assembly, comprising: a stationary jaw member having a proximal end and a distal end; a first jaw member having a first end pivotably coupled to the proximal end of the stationary jaw member and a second end; a second jaw member having a first end pivotably coupled to the distal end of the stationary jaw member and a second end, the first ends of the first and second jaw members being longitudinally spaced from one another along the stationary jaw member, wherein the stationary jaw member includes: a jaw housing; an insulator disposed on the jaw housing; and a conductive sealing surface disposed on the insulator. 